New discoveries offer possible Cushing’s disease cure

LOS ANGELES — More than a century has passed since the neurosurgeon and pathologist Harvey Cushing first discovered the disease that would eventually bear his name, but only recently have several key discoveries offered patients with the condition real hope for a cure, according to a speaker here.

There are several challenges clinicians confront in the diagnosis and treatment of Cushing’s disease, Shlomo Melmed, MB, ChB, FRCP, MACP, dean, executive vice president and professor of medicine at Cedars-Sinai Medical Center in Los Angeles, said during a plenary presentation. Patients who present with Cushing’s disease typically have depression, impaired mental function and hypertension and are at high risk for stroke, myocardial infarction, thrombosis, dyslipidemia and other metabolic disorders, Melmed said. Available therapies, which range from surgery and radiation to the somatostatin analogue pasireotide (Signifor LAR, Novartis), are often followed by disease recurrence. Cushing’s disease is fatal without treatment; the median survival if uncontrolled is about 4.5 years, Melmed said.

“This truly is a metabolic, malignant disorder,” Melmed said. “The life expectancy today in patients who are not controlled is apparently no different from 1930.”

The outlook for Cushing’s disease is now beginning to change, Melmed said. New targets are emerging for treatment, and newly discovered molecules show promise in reducing the secretion of adrenocorticotropic hormone (ACTH) and pituitary tumor size.

“Now, we are seeing the glimmers of opportunity and optimism, that we can identify specific tumor drivers — SST5, [epidermal growth factor] receptor, cyclin inhibitors — and we can start thinking about personalized, precision treatment for these patients with a higher degree of efficacy and optimism than we could have even a year or 2 ago,” Melmed said. “This will be an opportunity for us to broaden the horizons of our investigations into this debilitating disorder.”

Challenges in diagnosis, treatment

Overall, about 10% of the U.S. population harbors a pituitary adenoma, the most common type of pituitary disorder, although the average size is only about 6 mm and 40% of them are not visible, Melmed said. In patients with Cushing’s disease, surgery is effective in only about 60% to 70% of patients for initial remission, and overall, there is about a 60% chance of recurrence depending on the surgery center, Melmed said. Radiation typically leads to hypopituitarism, whereas surgical or biochemical adrenalectomy is associated with adverse effects and morbidity. Additionally, the clinical features of hypercortisolemia overlap with many common illnesses, such as obesity, hypertension and type 2 diabetes.

“There are thousands of those patients for every patient with Cushing’s disease who we will encounter,” Melmed said.

The challenge for the treating clinician, Melmed said, is to normalize cortisol and ACTH with minimal morbidity, to resect the tumor mass or control tumor growth, preserve pituitary function, improve quality of life and achieve long-term control without recurrence.

“This is a difficult challenge to meet for all of us,” Melmed said.

Available options

Pituitary surgery is typically the first-line option offered to patients with Cushing’s disease, Melmed said, and there are several advantages, including rapid initial remission, a one-time cost and potentially curing the disease. However, there are several disadvantages with surgery; patients undergoing surgery are at risk for postoperative venous thromboembolism, persistent hypersecretion of ACTH, adenoma persistence or recurrence, and surgical complications.

Second-line options are repeat surgery, radiation, adrenalectomy or medical therapy, each with its own sets of pros and cons, Melmed said.

“The reality of Cushing’s disease — these patients undergo first surgery and then recur, second surgery and then recur, then maybe radiation and then recur, and then they develop a chronic illness, and this chronic illness is what leads to their demise,” Melmed said. “Medical therapy is appropriate at every step of the spectrum.”

Zebrafish clues

Searching for new options, Melmed and colleagues introduced a pituitary tumor transforming gene discovered in his lab into zebrafish, which caused the fish to develop the hallmark features of Cushing’s disease: high cortisol levels, diabetes and cardiovascular disease. In the fish models, researchers observed that cyclin E activity, which drives the production of ACTH, was high.

Melmed and colleagues then screened zebrafish larvae in a search for cyclin E inhibitors to derive a therapeutic molecule and discovered R-roscovitine, shown to repress the expression of proopiomelanocortin (POMC), the pituitary precursor of ACTH.

In fish, mouse and in vitro human cell models, treatment with R-roscovitine was associated with suppressed corticotroph tumor signaling and blocked ACTH production, Melmed said.

“Furthermore, we asked whether or not roscovitine would actually block transcription of the POMC gene,” Melmed said. “It does. We had this molecule (that) suppressed cyclin E and also blocks transcription of POMC leading to blocked production of ACTH.”

In a small, open-label, proof-of-principal study, four patients with Cushing’s disease who received roscovitine for 4 weeks developed normalized urinary free cortisol, Melmed said.

Currently, the FDA Office of Orphan Products Development is funding a multicenter, phase 2, open-label clinical trial that will evaluate the safety and efficacy of two of three potential doses of oral roscovitine (seliciclib) in patients with newly diagnosed, persistent or recurrent Cushing disease. Up to 29 participants will be treated with up to 800 mg per day of oral seliciclib for 4 days each week for 4 weeks and enrolled in sequential cohorts based on efficacy outcomes.

“Given the rarity of the disorder, it will probably take us 2 to 3 years to recruit patients to give us a robust answer,” Melmed said. “This zebrafish model was published in 2011, and we are now in 2019. It has taken us 8 years from publication of the data to, today, going into humans with Cushing’s. Hopefully, this will light the pathway for a phase 2 trial.”

 Offering optimism’

Practitioners face a unique paradigm when treating patients with Cushing’s disease, Melmed said. Available first- and second-line therapy options often are not a cure for many patients, who develop multimorbidity and report a low quality of life.

“Then, we are kept in this difficult cycle of what to do next and, eventually, running out of options,” Melmed said. “Now, we can look at novel, targeted molecules and add those to our armamentarium and at least offer our patients the opportunity to participate in trials, or at least offer the optimism that, over the coming years, there will be a light at the end of the tunnel for their disorder.”

Melmed compared the work to Lucas Cranach’s Fons Juventutis (The Fountain of Youth). The painting, completed in 1446, shows sick people brought by horse-drawn ambulance to a pool of water, only to emerge happy and healthy.

“He was imagining this ‘elixir of youth’ (that) we could offer patients who are very ill and, in fact, that is what we as endocrinologists do,” Melmed said. “We offer our patients these elixirs. These Cushing’s patients are extremely ill. We are trying with all of our molecular work and our understanding of pathogenesis and signaling to create this pool of water for them, where they can emerge with at least an improved quality of life and, hopefully, a normalized mortality. That is our challenge.” – by Regina Schaffer

Reference:

Melmed S. From zebrafish to humans: translating discoveries for the treatment of Cushing’s disease. Presented at: AACE Annual Scientific and Clinical Congress; April 24-28, 2019; Los Angeles.

Disclosure: Melmed reports no relevant financial disclosures.

 

From https://www.healio.com/endocrinology/neuroendocrinology/news/online/%7B585002ad-640f-49e5-8d62-d1853154d7e2%7D/new-discoveries-offer-possible-cushings-disease-cure

Novel Therapy Eases Cushing’s Symptoms in Pivotal Trial

by Kristen Monaco, Staff Writer, MedPage Today

LOS ANGELES — An investigational therapy improved quality of life and reduced disease symptoms for patients with endogenous Cushing’s syndrome, according to new findings from the phase III SONICS study.

Patients taking oral levoketoconazole twice daily had significant reductions in mean scores for acne (-1.8), peripheral edema (-0.4), and hirsutism (-2.6), all secondary endpoints of the pivotal trial (P<0.03 for all), reported Maria Fleseriu, MD, of Oregon Health and Science University in Portland.

“We’re looking forward to see the results of further studies and to add this therapy to the landscape of Cushing’s,” Fleseriu said here during a presentation of the findings at AACE 2019, the annual meeting of the American Association of Clinical Endocrinologists. “We have a newer medication and still we cannot make a dent in the outcomes of Cushing’s, especially for patient-reported outcomes.”

Free testosterone levels significantly decreased in women taking levoketoconazole (a ketoconazole stereoisomer and potent steroidogenesis inhibitor), from an average of 0.32 ng/dL down to 0.12 ng/dL (0.011 to 0.004 nmol/L, P<0.0001). Men had a non-significant increase: 5.1 ng/dL up to 5.8 ng/dL (0.177 to 0.202 nmol/L).

There were no significant changes from baseline to the end of maintenance for other secondary endpoints in the analysis: moon facies, facial plethora, striae, bruising, supraclavicular fat, irregular menstruation, and dysmenorrhea. However, significant improvements after 6 months of therapy were seen in patient-reported quality of life compared with baseline (mean 10.6 change on the Cushing QOL questionnaire) as well as a significant reduction in depressive symptoms (mean -4.3 change on the Beck Depression Inventory II).

The open-label, multicenter SONICS (Study of Levoketoconazole in Cushing’s Syndrome) trial included 94 adult men and women with a confirmed diagnosis of Cushing’s syndrome and elevated 24-hour mean urinary free cortisol (mUFC) levels at least 1.5 times the upper limit of normal.

In the dose-titration phase of the study (weeks 2 to 21), patients were titrated up to a max dose of 600 mg levoketoconazole twice daily until mUFC normalization. A 6-month maintenance phase followed with no dose increases, but decreases were allowed if adverse events emerged. An additional 6-month extended evaluation phase followed thereafter.

The study met it’s previously reported primary endpoint, with 30% of patients achieving normalized mUFC levels after 6 months of maintenance therapy without a dose increase (95% CI 21%-40%, P=0.0154).

Levoketoconazole was well tolerated, with only 12.8% of patients discontinuing treatment due to adverse events. The most commonly reported adverse events were nausea (31.9%), headache (27.7%), peripheral edema (19.1%), hypertension (17%), and fatigue (16%), some of which were expected due to steroid withdrawal, Fleseriu said.

Serious adverse events were reported in 14 patients, including prolonged QTc interval in two patients, elevated liver function in one patient, and adrenal insufficiency in another, events similar to those seen with ketoconazole (Nizoral) therapy.

Fleseriu explained that drug-drug interaction is a problem in Cushing’s, as all of the available medications prolong QT interval.

She noted that in SONICS, QT prolongation with levoketoconazole was observed in few patients. It’s still a “concern,” said Fleseriu, especially for patients on other drugs that prolong QT.

Although not yet approved, levoketoconazole has received orphan drug designation from the FDA and the European Medicines Agency for endogenous Cushing’s syndrome. The tentative brand name is Recorlev.

The study was supported by Strongbridge Biopharma.

Fleseriu reported relationships with Strongbridge, Millendo Therapeutics, and Novartis. Co-authors also disclosed relevant relationships with industry.

From https://www.medpagetoday.com/meetingcoverage/aace/79465

Cyclic Cortisol Production May Lead to Misdiagnosis in Cushing’s

Increased cortisol secretion may follow a cyclic pattern in patients with adrenal incidentalomas, a phenomenon that may lead to misdiagnosis, a study reports.

Since cyclic subclinical hypercortisolism may increase the risk for heart problems, researchers recommend extended follow-up with repeated tests to measure cortisol levels in these patients.

The study, “Cyclic Subclinical Hypercortisolism: A Previously Unidentified Hypersecretory Form of Adrenal Incidentalomas,” was published in the Journal of Endocrine Society.

Adrenal incidentalomas (AI) are asymptomatic masses in the adrenal glands discovered on an imaging test ordered for a problem unrelated to adrenal disease. While most of these benign tumors are considered non-functioning, meaning they do not produce steroid hormones like cortisol, up to 30% do produce and secrete steroids.

Subclinical Cushing’s syndrome is an asymptomatic condition characterized by mild cortisol excess without the specific signs of Cushing’s syndrome. The long-term exposure to excess cortisol may lead to cardiovascular problems in these patients.

While non-functioning adenomas have been linked with metabolic problems, guidelines say that if excess cortisol is ruled out after the first evaluation, patients no longer need additional follow-up.

However, cortisol secretion can be cyclic in Cushing’s syndrome, meaning that clinicians might not detect excess amounts of cortisol at first and misdiagnose patients.

In an attempt to determine whether cyclic cortisol production is also seen in patients with subclinical Cushing’s syndrome and whether these patients have a higher risk for metabolic complications, researchers in Brazil reviewed the medical records of 251 patients with AI — 186 women, median 60 years old — followed from 2006 to 2017 in a single reference center.

Cortisol levels were measured after a dexamethasone suppression test (DST). Dexamethasone is used to stop the adrenal glands from producing cortisol. In healthy patients, this treatment is expected to reduce cortisol levels, but in patients whose tumors also produce cortisol, the levels often remain elevated.

Patients were diagnosed with cyclic subclinical Cushing’s syndrome if they had at least two normal and two abnormal DST tests.

From the 251 patients, only 44 performed the test at least three times and were included in the analysis. The results showed that 20.4% of patients had a negative DST test and were considered non-functioning adenomas.

An additional 20.4% had elevated cortisol levels in all DST tests and received a diagnosis of sustained subclinical Cushing’s syndrome.

The remaining 59.2% had discordant results in their tests, with 18.3% having at least two positive and two negative test results, matching the criteria for cyclic cortisol production, and 40.9% having only one discordant test, being diagnosed as possibly cyclic subclinical Cushing’s syndrome.

Interestingly, 20 of the 44 patients had a normal cortisol response at their first evaluation. However, 11 of these patients failed to maintain normal responses in subsequent tests, with four receiving a diagnosis of cyclic subclinical Cushing’s syndrome and seven as possibly cyclic subclinical Cushing’s.

Overall, the findings suggest that patients with adrenal incidentalomas should receive extended follow-up with repeated DST tests, helping identify those with cyclic cortisol secretion.

“Lack of recognition of this phenomenon makes follow-up of patients with AI misleading because even cyclic SCH may result in potential cardiovascular risk,” the study concluded.

From https://cushingsdiseasenews.com/2019/04/11/cyclic-cortisol-production-may-lead-to-misdiagnosis-in-cushings-study-finds/

The Incidence Of Cushing’s Disease: A Nationwide Swedish Study

In: Pituitary, ISSN 1386-341X, E-ISSN 1573-7403, Vol. 22, no 2, p. 179-186Article in journal (Refereed) Published

Abstract [en]

Background: Studies on the incidence of Cushing’s disease (CD) are few and usually limited by a small number of patients. The aim of this study was to assess the annual incidence in a nationwide cohort of patients with presumed CD in Sweden.

Methods: Patients registered with a diagnostic code for Cushing’s syndrome (CS) or CD, between 1987 and 2013 were identified in the Swedish National Patient Registry. The CD diagnosis was validated by reviewing clinical, biochemical, imaging, and histopathological data.

Results: Of 1317 patients identified, 534 (41%) had confirmed CD. One-hundred-and-fifty-six (12%) patients had other forms of CS, 41 (3%) had probable but unconfirmed CD, and 334 (25%) had diagnoses unrelated to CS. The mean (95% confidence interval) annual incidence between 1987 and 2013 of confirmed CD was 1.6 (1.4-1.8) cases per million. 1987-1995, 1996-2004, and 2005-2013, the mean annual incidence was 1.5 (1.1-1.8), 1.4 (1.0-1.7) and 2.0 (1.7-2.3) cases per million, respectively. During the last time period the incidence was higher than during the first and second time periods (P<0.05).

Conclusion: The incidence of CD in Sweden (1.6 cases per million) is in agreement with most previous reports. A higher incidence between 2005 and 2013 compared to 1987-2004 was noticed. Whether this reflects a truly increased incidence of the disease, or simply an increased awareness, earlier recognition, and earlier diagnosis can, however, not be answered. This study also illustrates the importance of validation of the diagnosis of CD in epidemiological research.

Place, publisher, year, edition, pages

SPRINGER , 2019. Vol. 22, no 2, p. 179-186

Keywords [en]

Cushing’s syndrome, Epidemiology, Incidence, Validation

National Category

Endocrinology and Diabetes

Identifiers

URN: urn:nbn:se:uu:diva-380429DOI: 10.1007/s11102-019-00951-1ISI: 000461291200010PubMedID: 30799512OAI: oai:DiVA.org:uu-380429DiVA, id: diva2:1300822

From http://uu.diva-portal.org/smash/record.jsf?aq2=%5B%5B%5D%5D&c=1&af=%5B%5D&searchType=LIST_LATEST&sortOrder2=title_sort_asc&query=&language=en&pid=diva2%3A1300822&aq=%5B%5B%5D%5D&sf=all&aqe=%5B%5D&sortOrder=author_sort_asc&onlyFullText=false&noOfRows=50&dswid=-3880

 

Osilodrostat Continues to Show Promise for Cushing’s Disease

NEW ORLEANS — The investigational drug osilodrostat (Novartis) continues to show promise for treating Cushing’s disease, now with new phase 3 trial data.

The data from the phase 3, multicenter, double-blind randomized withdrawal study (LINC-3) of osilodrostat in 137 patients with Cushing’s disease were presented here at ENDO 2019: The Endocrine Society Annual Meeting by Beverly M.K. Biller, MD, of the Neuroendocrine & Pituitary Tumor Center at Massachusetts General Hospital, Boston.

“Osilodrostat was effective and shows promise for the treatment of patients with Cushing’s disease,” Biller said.

Osilodrostat is an oral 11β-hydroxylase inhibitor, the enzyme that catalyzes the last step of cortisol biosynthesis in the adrenal cortex. Its mechanism of action is similar to that of the older Cushing’s drug metyrapone, but osilodrostat has a longer plasma half-life and is more potent against 11β-hydroxylase.

Significantly more patients randomized to osilodrostat maintained a mean urinary free cortisol (mUFC) response versus placebo at 34 weeks following a 24-week open-label period plus 8-week randomized phase, with rapid and sustained mUFC reduction in most patients.

Patients also experienced improvements in clinical signs of hypercortisolism and quality of life. The drug was generally well-tolerated and had no unexpected side effects.

Asked to comment, session comoderator Julia Kharlip, MD, associate medical director of the Pituitary Center at the University of Pennsylvania, Philadelphia, told Medscape Medical News, “This drug is incredibly exciting because over 80% of people were controlled fairly rapidly. People could get symptom relief but also a reliable response. You don’t have to wonder when you’re treating a severely affected patient if it’s going to work. It’s likely going to work.”

However, Kharlip cautioned that it remains to be seen whether osilodrostat continues to work long-term, given that the older drug metyrapone — which must be given four times a day versus twice daily for osilodrostat — is known to become ineffective over time because the pituitary tumor eventually overrides the enzyme blockade.

“Based on how osilodrostat is so much more effective at smaller doses, there’s more hope that it will be effective long term…If the effectiveness and safety profile that we’re observing now continues to show the same performance years in a row, then we’ve got our drug.”

Osilodrostat Potentially Addresses an Unmet Medical Need

Cushing’s disease is a rare disorder of chronic hypercortisolism with significant burden, increased mortality, and decreased quality of life. Pituitary surgery is the recommended first-line treatment for most patients, but not all patients remit with surgery and some require additional treatment.

Pasireotide (Signifor, Novartis), an orphan drug approved in the United States and Europe for the treatment of Cushing’s disease in patients who fail or are ineligible for surgical therapy, is also only effective in a minority of patients.

“There hasn’t been a medicine effective for long-term treatment, so a lot of patients end up getting bilateral adrenalectomy, thereby exchanging one chronic medical disease for another,” Kharlip explained.

Biller commented during the question-and-answer period, “I think because not all patients are placed in remission with surgery initially and because other patients subsequently recur — a problem that is more common than we used to believe — we do need medical therapies.”

She continued, “I think it’s important to have a large choice of medical therapies that work in different places in the hypothalamic-pituitary-adrenal axis.

“Even though surgery is the right initial therapy for everyone, I think in terms of subsequent medical therapy we have to tailor that to the individual circumstances of the patient in terms of the goals of treatment, and perhaps what other medicines they’re on, the degree of cortisol excess [and other factors].”

Highly Significant Normalization in Mean UFC Versus Placebo

In a prior 22-week phase 2 study (LINC-2), osilodrostat normalized mUFC in most patients. Results of the extension phase were reported by Medscape Medical News 2 years ago.

The current phase 3 study, LINC-3, was conducted on the basis of that proof-of-concept study, Biller said.

The trial was conducted in 19 countries across four continents in patients with persistent or recurrent Cushing’s disease screened for mUFC > 1.5 times the upper limit of normal and other entry criteria. In total, 137 patients were enrolled and randomized.

Participants were a median age of 40 years, 77% were female, and 88% had undergone prior pituitary surgery. Nearly all (96%) had received at least one previous treatment for Cushing’s.

At baseline, patients’ mean mUFC (364 µg/24 hours) was 7.3 times the upper limit of normal, which is “quite significant hypercortisolemia,” Biller noted.

All patients initially received osilodrostat, with a rapid dose uptitration every 2 weeks from 2 to 30 mg orally twice daily until they achieved a normal UFC.

They continued on open-label medication until week 24, when urine samples were collected. Patients who had an mUFC less than the upper limit of normal and had not had a dose increase in the prior 12 weeks were eligible for the double-blind phase. Those who were ineligible continued taking open-label drug.

The 70 eligible patients were randomized to continue taking osilodrostat (n = 36) or were switched to placebo (n = 34) for another 8 weeks. After that, the patients taking placebo were switched back to osilodrostat until week 48. A total of 113 patients completed the 48 weeks.

The primary efficacy endpoint was mUFC at 34 weeks (the end of the 8-week randomized phase).

For those randomized to continue on the drug, mUFC remained in the normal range in 86.1% of patients versus just 29.4% of those who had been switched to placebo for the 8 weeks. The difference was highly significant (odds ratio, 13.7; P < .001), Biller reported.

A key secondary endpoint, proportion of patients with an mUFC at or below the ULN at 24 weeks without up-titration after week 12, was achieved in 53%.

The mean dose at 48 weeks was 11.0 mg/day, “a fairly low dose,” she noted.

Clinical features were also improved at week 48, including systolic and diastolic blood pressure (percentage change –6.8 and –6.6, respectively), weight (–4.6), waist circumference (–4.2), fasting plasma glucose (–7.1), and HbA1c (–5.4).

Scores on the Cushing Quality of Life scale improved by 52.4 points, and Beck Depression Inventory scores dropped by 31.8 points.

Most Adverse Events Temporary, Manageable

The most commonly reported adverse events were nausea (41.6%), headache (33.6%), fatigue (28.5%), and adrenal insufficiency (27.7%), and 10.9% of patients overall discontinued because of an adverse event.

Adverse events related to hypocortisolism occurred in 51.1% of patients overall, with 10.2% being grade 3 or 4.  However, most of these were single episodes of mild-to-moderate intensity and mainly occurred during the initial 12-week titration period. Most patients responded to dose reduction or glucocorticoid supplementation.

Adverse events related to accumulation of adrenal hormone precursors occurred in 42.3% of patients overall, with the most common being hypokalemia (13.1%) and hypertension (12.4%).

No male patients had signs or symptoms related to increased androgens or estrogens. However, 12 female patients experienced hirsutism, most of those patients also had acne, and one had hypertrichosis. None discontinued because of those symptoms.

Kharlip commented, “What’s really inspiring was that even though half of the patients had symptoms related to adrenal insufficiency, it sounded as if they were quickly resolved with treatment and none discontinued because of it.”

“And it may have been related to study design where the medication was titrated very rapidly. There is probably a way to do this more gently and get the good results without the side effects.”

Kharlip also praised the international consortium that devised the protocol and collaborated in the research effort.

“It’s incredibly exciting and gratifying to see the world come together to get these data. It’s such a rare disease. To be able to have something like that in the field is a dream, to have a working consortium. The protocol was effective in demonstrating efficacy. It’s just a win on so many levels for a disease that currently doesn’t have a good therapy…I struggle with these patients all the time so I’m thrilled that there is hope.”

An ongoing confirmatory phase 3 study, LINC-4, is evaluating patients up to 48 weeks.

Biller is a consultant for and has received grants from Novartis and Strongbridge. Kharlip has  reported no relevant financial relationships.

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From https://www.medscape.com/viewarticle/910864#vp_1

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